1. Field of the Invention
The present invention relates to a copying apparatus, and more specifically, to an electrophotographic copying apparatus provided with an automatic document feeder and a finisher having a function of binding copies.
2. Description of the Related Art
Recently, in reference to an electrophotographic copying apparatus, users have been demanding for the automation of handling originals and copy sheets. At the request, an automatic document feeder for feeding a stack of originals onto an original glass one after another and discharging the originals from the original glass serially after the image exposure, a finisher for stacking and aligning copies automatically and stapling the copies with an electric stapler and so on have been provided in various types.
Incidentally, such a finisher has a limitation in stapling copies, and a stapling tray is limited in capacity in accordance with the limitation of the finisher. In the meantime, an automatic document feeder has a capacity to handle more originals at one time than copies to be handled by the finisher. For example, in a copying apparatus provided with a stapling tray which has a storing capacity of 30 and an automatic document feeder which has a handling capacity of 50, when more than 30 originals are to be copied, a stapling mode should be canceled to eject copies onto an ordinary sheet tray.
Also, these days, a type of automatic document feeder having a function of tuning over originals has been developed, and in a copying apparatus provided with such an automatic document feeder, when the images on the both sides of each original are to be copied on different sheets, 15 originals will produce 30 copies which is the limitation of the finisher. On the other hand, when two images of two originals are copied onto the both sides of a copy sheet, 30 originals will be produce only 15 copies.
Therefore, the judgment of availability of the staping operation based on only the number of originals will fail to follow the recent image handling in various operation modes.